Burster



Dec. l5, 1964 R. M. PINE ETAL BURSTER 6 Sheets-Sheet 1 Filed July 19, 1962 Dec. 15, 1964 R. M. PINE ETAL 3,161,335

BURSTER Filed July 19, 1962 6 snee 2 Dec. 15, 1964 R. M. PINE ETAL BURSTER 6 Sheets-Sheet 3 Filed July 19. 1962 Dec- 15, 1964 R. M. PINE ETAI.

BURSTER Dec. 15, 1964 R. M. PINE ETAL BURSTER 6 Sheets-Sheet 5 Filed July 19, 1962 @EFL NN @wk Dec. 15, 1964 R. MA PINE ETAL BURSTER Filed July 19. 1962 6 Sheets-Sheet 6 mfmzl United States Patent O 3,161,335 IEIJRS'IER vRobert Ml. Fine, Chicago, and Donal-d Ji. Steidinger, Clarendon Hills, Ill., assignors to Uarco, Incorporated, a corporation of Iliinois Filed .luly I9, 1%2, Ser. No. 216,982 lil Claims. (Cl. 22S-Idil) This invention relates to mechanisms for processing continuous form stationery and more particularly to a device for separating continuous form stationery into individual form lengths.

A problem currently present in machines for bursting continuous form stationery into individual form lengths is the tendency of the stationery being fed through the burster to buck1e, jam or tend to travel a nonlinear path through the burster machine. The transverse lines of weakening in such stationery tend to complicate the problem. Much difficulty has been encountered when attempting to run at relatively high speeds particularly since the common method of driving stationery through a burster is by frictional engagement between two vertically spaced pairs of cooperating rollers running at different speeds in order to separate the form lengths from the balance of the strip.

In those bursters where Hats or other recesses have been formed on driving rollers in an attempt to allow stationery to pass freely between the rollers periodically, there has been a tendency for an uneven rate of paper feed to result since the faster rolls may be feeding the strip at the time the slower rolls release their grip on the strip. Uneven feeding will also cause buckles and ripples in the stationery surface and give rise to possible creasing of the stationery and jamming of the machine.

It is therefore an object of this invention to provide a new and improved burster device.

It is another object of this invention to provide a new and improved burster wherein the stationery is urged without gripping to follow a generally linear path throughout the device.

It is another object of this invention to provide a new and improved burster wherein the vertical movement of the stationery is limited throughout the entire path of travel of the stationery through the machine without impeding the horizontal flow of the stationery.

It is yet another object of this invention to provide a new and improved burster wherein the continuous strip of stationery is fed through the first pair of burster rolls at a uniform rate of travel.

Another object is to provide a novel arrangement in the cooperating pairs of rolls of a stationery burster for causing the pairs of rolls to release a driving relation with the stationery in a predetermined timed relation.

It is a further object of this invention to provide a new and improved burster having an intermediate roller unit horizontally adjustable with relation to a yiixed position rear roller unit to vary space between the bights of the roller units for various form lengths of stationery.

It is still a further object of this invention to provide a new and improved burster wherein the intermediate roller unit is horizontally adjustable in the line of paper travel and self-locking at any preselected position.

It is a yet further object of this invention to provide a new and improved burster wherein a rear roller unit is xed in position in the burster and a roller of the rear roller unit has a plurality of longitudinal flats formed thereon, and the intermediate roller unit is horizontally adjustable in the direction of paper travel and self-locking in any adjusted position, and a roller of the intermediate roller unit also has a plurality of longitudinal flats, and the intermediate roller unit is driven at a reduced speed relative to the rear roller unit in such a fashion that whenever the intermediate roller unit is out of gripping contact with the stationery, the individual rollers of the rear roller unit are also out of contact with the stationery.

Other objects, features, and advantages of the present invention will be readily apparent from the following description of the preferred embodiment illustrated in the accompanying drawings, in which:

FIGURE l is a broken side elevational view partially diagrammatic of a burster mechanism embodying this invention;

FIGURE 2 is a broken, enlarged top elevational view of a portion of the device of FIGUREl with parts removed for clarity of illustration;

FIGURE 3 is an upright section view taken along the line 3--3 of FIGURE 2;

`FIGURE 4 is a section view taken along the line 4 4 of yFIGURE 3 through the feed-in mechanism;

FIGURE 5 is a section View taken along the line 5*-5 of FIGURE 2 through the rst pair of cooperating burster rolls;

FIGURE 6 is a section view taken along the line @-6 of FIGURE 5;

FIGURE 7 is a section view taken along the line 7-7 of FIGURE 2 through the second pair of cooperating burster rolls;

FIGURE 8 is an enlarged fragmentary view of a portion of FIGURE 2 illustrating a portion of the stationery guiding means;

FIGURE 9 is a section view taken along the line 9-9 of FIGURE 8;

FIGURE l0 is a fragmentary section view taken along the line lid-itl of FIGURE 3 showing a part of the breaker roll assembly;

FIGURE ll is an enlarged fragmentary View taken along the line lll- II of FIGURE 5 through a portion of the adjusting means for the burster rolls shown in FIGURE 5; and

FIGURE l2 is an enlarged View of the structure shown in FIGURE ll taken along the line lll-l2 of FIGURE 5.

As shown in FIGURE l, the burster mechanism I() of this invention is included in a frame 11 of generally boxlike conguration. The burster is adapted to receive a Zig-zag folded stack I2 of continuous form stationery I3 at its front end lila and means are provided for driving the stationery in the direction indicated by the arrow A in FIGURE l. The stationery is fed through the front infeed roller unit 1,4 and driven through an intermediate roller unit 16 and rear roller unit 18 which mutually cooperate to separate or burst the continuous form stationery into individual form lengths by separating it along its transverse lines of weakening. The individual form lengths are then ejected at the rear ltlb of the burster.

Mounted within the frame I1 and shown in phantom outline in FIGURE 1 are a motor Ztl and belt 24 which mutually cooperate to drive a pulley wheel 22, the belt passing by an idler 23 which acts to suitably adjust the tension of the belt. The pulley 22 is secured to one end of the lower rear roller shaft 26 which is part of the rear roller unit I8. Roller shaft 26 extends across the path of travel of the stationery and is spaced therebelow. As shown in FIGURE 7, at the other end of the shaft 26 there is a spur gear 28 mounted coaxially with shaft 26 and having a plurality of radially outwardly projecting teeth. The spur gear Z8 is in meshing engagement with a Worm 3i) mounted on a driven shaft 32 of generally hexagonal peripheral configuration which extends in the direction of paper travel or transverse to the longitudinal extent of the shaft 2.6. The driven shaft 32 is journalled for rotation in a sleeve 29 which is fitted in a housing member 76 which forms one side of the rear roller unit 18. The gear 23 and v and 36. These racks are so positioned in theV burster as to be spaced from either edgey ofV the stationery 13 and therefore lie outside of the path of stationery travel.v As will be explained later, they secure theV roller units 14, 16 and 18 in the burster as wellaspermitting linear movement of the unit 16 in the line of paper travel.

As shown in FIGURES 2, 3` and 4'the` front infeedV roller unit 14 consists of'a lower circular cylindr1cal driven roller 38rof hard material, such as steel, mounted on a shaft 39a below the line of paper vtravel and extend- 14 and below the line of stationery travel is the rod securing bar 61a to which the front ends 57a` of the rods 56a arefsecured by the clamp 64. The rear end 57d f. of the rod 5617 is downturned inra direction generally normal to Vthe .longitudinal extent of the rod 56h and restsagainstthe rear rod securing meansr62 which extends across the'y rear roller unit 18. Thus the, stationery is provided with a base support throughout the length of its travel through vthe burster after leaving the infeed roller unit 14. The rear strip securing bar 65a extends across the rear roller unit 185 behind the rollers Vth'ereinfor securing the strip 58 thereto by means' such ing thereacross. Apair of relatively narrowrubber wheels 40 and 40a are rotatably mounted together. with a shaft 42 spaced above the shaft 39a and above the line of paper travel so that .portions of the periphery of the rollers 40 and 49a are in contact with the portions of the periphery of the driven roller 38( forV providing driven Vinfeed means for stationery entering the burster between rollerY 38 and wheels 40 and 40a. The. wheels rotate by Y virtuel of the contact with moving stationery on the roller 38. The shaft 42 is mounted for limited verticall movement Vin a pair of slots 41 and 41a secured by appropriate means, such as screws 43, to housing members 44v and 44a at each end of the shaft 42. By mounting the shaft 42 for limited vertical .movement the upper roller wheels 40 and 40a may respond to non-horizontal surface portions of the stationery 13,'such asV are'caused by creases or by the transverse lines of weakening, by c being vertically displaced without limiting the flow of paper infeed and thereby aiding constant paper speed into the burster.

Tie rods,fsuch as 46, join the housing members 44Y and 44a to form the unit 14. Each housing member is secured to the racks 34 and 36' by appropriate means,

such as screws 45, to secure the unit in the burster at a xed position. The shaft 39a which mounts thefrollerV 38 is journalled for rotation in the housings by means of bearings 39. Mounted at one end of the shaft 39a and'outside the housing 44 is a wormv wheel 59 which in turn is in operational meshing engagement with the infeed worm gear 48 secured to the driven shaft 32. The rotation of the driven shaft 32, and therefore the worm 48, vdrives the roller 38 by means ofthe worm wheel 50, in a direction to feed the paper to the bursting rolls'.` Extending in the direction of paper flow and mounted as a screw 68 as shownin FIGURES. This provides the stationery 13 with a vertical deflection means from the point of the upstanding mounts. 59 throughout the remainder of the path oftravel of the stationery through the burster. The strips 53 are secured to the bar 66 by means' of a removable clamp 70 ywith the free end portion 58a extending out yas shown in FIGURE 9. The clamp 70 permits the tape to be secured to the bar 66 but allows the tapefto be adjusted for tension. By pulling the free rend. 58a thel tape 58 will decrease in length v between bars 66 and 66a and, therefore increase ,intension and the clamp 7.will retain the tape in the posi- Vtion of jincreased tension without permitting slippage thereof. By pulling on the portion of the tape between thel bars 66 and e641 the end Sa will slip in the opposite direction and the tape ywill decrease in tension. Thus the tape V5 8: may be adjusted'for tension to increase or,v decrease its dampening effect on Vstationery passing between the tape 58 and the rod '56. Y

. The rear roller unit 18 includes anfupper. drive roller 72 above lthe path of stationery travel and a lower drive roller 74. below the path of stationery travel. The rollers 72 and 74 extend transverse. to the directiony of paper travel and are journalled for rotation in bearings 78 resting upon springs 77a holding the shaft lup against adyjusting screws 77 whichl 'project downwardly therein against the mountings 78. Tie rods8tl extend between the housing member 76 and 76a to form a unitary structure.

above and below the line of paper travel are the spaced Y separate sections 56a and 56b. Also included in support means 54 are a plurality of vertical deflecting means or tapes or strips 58 of resilient flexible material, suchy as mylar, verticallyspaced above each ,-rod. As' the stationery 13 travels through the burster it'maintains a` Vgenerally line` contact tangent to the Vperiphery of the rods 56a and 56h. The ,vertically spaced mylar strips 58 dampen vertical movement of the stationery 13 Without limiting horizontal movement thereof. Thus the spaced support means54 forms a paper guiding channelwhich aids' the flow of paper through the machine and also promotes constant feeding thereof. Extending generally normal to the racks 34 and 36 and secured thereto by means such as screws 60, are the upstanding securing Barmounts-59 and 59a. l con the mounts' 59Kand. 59a and extending across the path of travel of the stationery and, spaced therebelo'w is the Positioned The housing members 76 and 76a are secured to the racks 34 and .36, respectively, by appropriate means, such as screws 2,.to position the Vrear outfeed roller unit in the burster. Coaxially journalled on the shaft 26 at the same end as the pulley 22 is a drive transfer spur 'gear 85 which meshes with the drive receiving spur gear 86 mounted on'shaft 84 and is vertically alignedy therewith for driv- Ving the upperroller'72 at the same peripheral speed as the lower roller 74.

Rollers 72 and 74 have circumferentially relieved areas such as 90 and 91, respectively, which form enlarged passages 93 through which the strips 58 and the ends'57d ofthe rods 56d may pass without interfering with the rotation of the rolls. Rollers 72 and 74 have, circumferenrod securing bar,61 to which the rear ends 57a of the rods 56a and the front ends 57b of the rods 56h are secured by removable means, such as clamps 64. VExtending transversely across the rear of the front infeed unit tial area 92 and 94, respectively, which are normally in peripheral surface Contact as shown at 95 in FIGURE 7 for rearward feeding of separated stationery passed there between.l However, the roller 72 is provided with a series of longitudinally extending at or recesses 96 and 98 which are formed on the circumferential areas 92' 'thereby periodically forming a gap between the periphery ofthe roller 72Yand the periphery of the roller 74. Thisspace allows stationery to pass between .the

I peripheral contact with the roller 74. Due to the timing of the' gaps in therollers 72 and 74 with the gaps in the intermediateroller (unit 16),. the rear roller unit does,

not inuence the rate of stationery feed into the infeed unit 14 and/ or the roller unit 16.

The intermediate or rst burster roller unit 16 includes an upper roller 102 positioned above the path of paper travel and mounted on a shaft 103 extending transverse to the line of paper travel, and a lower roller 104 positioned below the path of paper travel and mounted on a shaft 105 parallel to shaft 103. Each end of the shafts is journaled for rotation in bearings 188 fitted in the housing members 106 and 106g and carried by a spring 109g opposed to adjusting screws 109.

Tie rods 118 pass between the housing members 106 and 106a to secure them into a single unit. The upper roller 102 is positioned in the housing by means of vertically extending screws 109 which pass through the housing and against the bearings 108 at the ends of the shafts 103. The shaft 105 has a drive receiving worm wheel 112 mounted coaxially thereon at the end adjacent the driven shaft 32 for cooperating with the worm 110 on the shaft 32 to receive the driving force therefrom for driving the roller 104. At the end of the shaft S opposite the gear 112 there is a drive transferring spur gear 114 which cooperates with the vertically aligned drive receiving spur gear 116 mounted on the end of the shaft 103 to transmit the driving force to the upper roller 102 and drive the lower and upper rollers at a common peripheral speed. The ratio of the gear teeth on the gear 112 and the worm 110 is such that the rollers 104 and 102 are driven at half the speed of the rollers "72 and 74 in the unit 18 for a purpose to be explained later.

The rollers 102 and 104 have circumferentially relieved areas 120 and 121, respectively, which form enlarged openings 119 therebetween to allow the passage of the strips 58 and the rods 56!) therethrough. The rollers 102 and 104 also possess circumferential areas 122 and 123, respectively, which are closely spaced from each other to drive paper therebetween without interfering with slight ripples or bubbles in the surface of the paper. At the ends of the roller 102 there are non-relieved areas 125 which are and remain in peripheral contact with areas 123 of the roller 104. The roller 102 possesses one longitudinally extending series of flats or recesses 124 on the areas 122. Because the rollers in the roller unit 16 are driven at half the speed of the rollers in the roller unit 18, the ats 124 on the roller 102 may be originally set and thereafter will always be opposite the periphery of the roller 104 when either the ats 96 or 98 of the roller 72 are opposite the periphery of the roller 7 4. Thus one per every revolution of the rollers 102 and 104 an twice per every revolution of the rollers 72 and '74 there will be a period of time when the stationery is not being driven by either the roller units 16 or 18. This lack of driving engagement between the rollers and the stationery permits any vertical misalignment of the stationery, such as surface buildups in front of the rollers or bubbles or other irregularities, to be smoothed out while maintaining a constant rate of paper feed, thereby aiding the continuous, even flow of the stationery through the mechanism.

Secured at the rear of the unit 16 between the roller units 16 and 18 is a stationery breaker means 126. Breaker means 126 includes a mounting bar 128 extending transverse to the direction of paper travel and mounted thereabove on the housing 106 and 106e by mounting screws 130. Spaced below the line of paper travel is a rotatable breaker roller shaft 134 which has a plurality of breaker rollers 132 mounted thereon for manual movement longitudinally thereof. The rollers 132 are so mounted so that portions of their peripheries extend slightly above the line of paper travel causing the paper to be deflected slightly vertically upward at this point. This vertical deflection causes an increase in tension of the stationery over the breaker when the stationery is taut and as the transverse line of weakening passes this point the driving engagement of the rear roller unit 1S will cause the stationery to be torn progressively evenly along that line creating the burst or separation of the individual form lengths from the remainder of the continuous form stationery. The separated form is then thrust rearwardly out of the burster by the rear roller unit 18. As shown in FiGURE l0, the end rollers, such as 132b, located at either end of the shaft 134 and outside the line of paper travel are adapted to receive a roller receiving and adjusting screw 136 which descends downwardly from the mounting bar 128 into the roller 13217. A similar construction, not shown, is found at the opposite end for roller 132:1. Thus the breaker roller shaft 134 is secured to the mounting bar 128 by means of these screws 136 passing into the end rollers 132a and 132i). The screws 136 also serve the function of adjusting the vertical position of the shaft 134, and therefore the breaker rollers 132 thereon7 which is accomplished by turning the screw 136 clockwise or counterclockwise to raise or lower the bar 134 relative to the stationery. The securing and adjusting screw 136 is frictionally bound in a preselected position by means of the pressure exerting screw 1318 which extends into the end rollers generally normal to the screw 136 and in abutting relation thereto. Loosening the set screw 138 frees the securing and adjusting screw for repositioning, and tightening the set screw 138 locks the securing and adjusting screw 136 in the desired position.

Also positioned on the roller unit 16 is the intermediate roller unit positioning and locking means 140. Means 140 is positioned on the unit outside the path of stationery travel and on the same side of the burster as is the pulley 22. Included in the means 140 is a motor 142 which is secured to a motor frame 143 fastened below the housing 10M by means, such as bolts 145. The motor 142 is operatively connected by conventional gearing means with a worm 144 which has its longitudinal axis vertically positioned generally normal to the rack 36. The worm 144 is in operable meshing engagement with pinion gear 146, the axis of which is generally parallel with the axis of the rollers 102 and 104 of the unit 16. By means of gear hub 147, the gear 146 is mounted at one end of a driving rod 148 which extends across the unit 16 transverse to the direction of paper flow and substantially parallel to and below the rollers 102 and 104. The driving rod 148 has two free ends, 148e and 14812, which operably mesh with the toothed surfaces of the racks, such as 34a, for moving the roller unit 16 horizontally along the length of the racks 34 and 36, and therefore in the line of paper travel, in response to actuation from the motor 142 transmitted through the Worm 144 to the gear 146. The rod 148 is journalled for rotation in sleeves, such as 149, formed in the housing members. It may be desirable to form the rod 148 of two sections for easy insertion and removal and in such cases a rod splicing sleeve 152 is provided for unifying the two elements of the rod 148 into one.

The intermediate worm gear is adapted for lateral movement relative to the driven shaft 32. This is accomplished by providing the worm 110 with an interior configuration for mating with the hexagonal peripheral configuration of the driven shaft 32, permitting the worm to slide relative to the shaft 32 but adapting it to receive and transmit rotational movement imparted to it by the shaft 32. By so constructing the Worm 110 the roller unit 16 may be moved horizontally along the line of paper travel by the aid of the positioning means without turning the rollers 102 and 104 and therefore without interfering with the timed relationship between the longitudinal flats 124 of the roller 122 in unit 16 and the flats 96 and 98 of the roller 72 in unit 18. Furthermore, because the worm of the positioning means 140 is mounted on the shaft of the motor 142 and adapted to drive the gear 146 the positioning means 140 is self-locking due to the fact that the gear is not capable of turning the worm in response to external actuation, such as machine vibration, manual pressure or the like. Thus the roller unit 16 may be Vhorizontally positioned4 along the length of the rack between preconstructed limitssuch as the mounting bar S9, and an appropriate distance from the rear unit 18, and

when traversed to the desired position the unit' will be automatically locked in that position. Also, due to the fact that the vertically adjustable breaker means is secured to unit 16 .this aords a horizontal adjustment for the breaker means.

As shown in FIGURE 1, the burster unit is provided with a front shelf 154 which issecured to the burster by hinges 156 so that the shelf 154 may be folded upV and become a part of the front wall of the( burster when not in use. A rear shelf 158 for receiving the separate individual form lengths of stationery is provided with removable paper guides 160 to dene lateral limits of the stack of individual form lengths received on the shelf 15S. rfhe shelf 158 is mounted at-162 to the vertical adjusting means 164 which is a part of the rear door 166.Y The door V166 is mounted on the burster by hinges 16S so that it may be swung about the hinges and form a part of the back wall of the burster whenV its associated apparatus is not in use. Prior to closing the rear door 166 the paper guides'are removed from the shelf 15:'8 and the shelf is lowered. The vertical adjusting means 164. is lowered an appropraite distance so the components of the door 166 may be received in the interior of the burster without interference when the door 166 is closed. y

This new and improved burster will urge the stationery being fed therethrough in a vertically limited linear'path. The provision for Vthe resilient'stationery deflecting strips throughout the run of the stationery through the machine retains the stationery withina given Yvertical limit Vso that no significant buckling will occur. Moreover, this is accomplished without hindering the horizontal progress of the stationery through the burster. Also/this burster maintains a constant rate of paper feed by having the flat portion of the front and rear bursting rollers timed. This insures that the rear bursting roller will not influence Vthe 4rate of stationery feed and thus serves to eliminate the problem of uneven feed as a factor in burster operation. The two pairs of bursting rolls may be positioned a distance apart for various different form or ticket lengths of stationery by manual control of the electric motor Vfor moving the intermediate set of rollers. Adjustment may be made while bursting Vis going on should slight movement of the intermediate rollers be desirable. Some adrollers and extending perpendiclrllar to the longitudinal axis of said rollers; a ysecond pair of coacting rollers operatively associated with said driven shaft and driven at a reduced speed relative to said first rollers, said Second pair -of rollers also having surfaces normally in contact and also geared together, for rotation at a common peripheral speed, said second pair of rollers also having a plurality of longitudinally'extending recesses of a number which in relation to the number of flats of said first pair of rollers equals the ratio of the speed between the two pairs of rollers; a plurality of spaced stationery supports, said spaced supports including a plurality of rodsV having theirlongitudinal extent extending in, they direction of stationery travel and being in line-contact with. the underside of the stationery, said supports also including aexis ble strip superposed above said rods and being held at each end in spaced relation to the rods, said flexible Ystrip being adjustable ineffective length therebetween with intermediate portions thereof flexible to allow the member to rise and fall in relation to the rods to urge the stationery towards the rods but not limit Ithe travel of stationery through the bursting machine.

2. The deviceof claim 1 wherein said supports extend through both sets of coacting rollers, one set of which is movable in the directionof paper travel.

3. The device of claim. 1 wherein the ends of said supports are held at a point beyond the extent of movement of the said rollers.

4. The device of claim 1 wherein said supports run continuously through both setsof rollers,V the flexible vmember being tape whichris held at one end to a bar by er; a second pair of coacting rollers operatively associated justnient may be indicated should the cross lines of weakening not coincide with the crest of the breaker rolls, for.

be lowered over the ytop of thefrrolls during most operations. There is no need to insert ones hands about thel burster rolls for feeding the stationery initially since the feed-in rolls and guides .accomplish the feeding. Some access may be needed for adjusting tension in the paper guide stripsor for adjusting the breaker roll height. or

Vlocation so that any cover is preferably hinged for convenient opening. A transparent cover also serves for carrying indicia indicating position of the intermediate burster rolls-for forms of different lengths.

thereof.

The foregoing description has been given for the clearl p ness of understanding only and no unnecessary limitations A weakening, comprising: a frame, a rst pair of driven,

coacting rollers in said frame, said irst pair of driven with said driven shaft and driven at a reduced speed relative to thel rst rollers, said second pair of rollers also having surfaces normally Vin contact and also geared together for rotation at a commonrperipheral speed, said second pair of rollers also having a plurality of longitud inally extending recesses of a number which in relation to the number of recesses in the rst pair of rollers equals the ratio of the speed between the two rollers; and positionin'gand locking means for moving said second pair of rollers in preselected positions along the line of stationery travel through the machine and automatically locking said second pair of rollers in said selected positions simultaneously. with the cessation of movement f 6. The device of claim 5 wherein said second pair of rollers is movable in the direction of paper travel and said rollers have at least one longitudinally extending recess in timed relationship to the rst roller recesses; Vand said second pair of roller is operatively associated with said driven shaft so that the timed relationship between the first and secondy roller recesses is maintained upon movement. of said second pair of rollers in the direction s of paper travel. 7. A bursting machine for'bursting continuous form Stationery into form lengths between transverse. lines of weakening, comprising: .a frame, a rst pair of driven corollers having surfaces normally incontact with a plun rality of longitudinally extending recessesV and being geared 'Y together for rotation in a common peripheral rate; a

driven shaft operatively associated .with said rstpair of Aacting rollers in said frame, said rst pair of driven rollers mounted transverse to the path of paper flow and having surfaces normally in contactwith a plurality of longitudinally extending'recesses and being geared together for rotation at a common peripheral rate; a driven shaft 'operatively associated with said first pair of rollers and extending perpendicular tothe longitudinal axis of said rollers; a second pair of coacting rollers parallel to said rst rollers operatively associated with said driven shaft to be driven at a reduced speed relative to said rst rollers, said second pair of rollers also having surfaces normally in contact and also geared together for rotation at a cornmon peripheral speed, said second pair of rollers also having a plurality of longitudinally extending recesses of a number which, in relation to the number of recesses of said irst pair of rollers, is a ratio equal to the ratio of the speed between the two rollers; a rack extending in the direction of paper travel; positioning and locking means for moving said second pair of rollers in preselected positions along the line of stationery travel and automatically locking said second pair of rollers in said selected positions simultaneously with the cessation of movement thereof, said means including a motor on said second pair of driven rollers and a pinion gear driven by said motor and in engagement with said rack to move said second pair of rollers in the direction of paper travel in response to actuation from said motor.

8. The device of claim 7 wherein said pinion gear is driven by said motor by means of a worm gear `so that said second pair of rollers is self-locking when positioned at any point along the longitudinal extent of said rack.

9. The device of claim 7 wherein said second pair of rollers is movable as a unit in the direction of paper travel; and said second pair of rollers is operatively associated with said driven shaft by means of a worm gear collar slidable longitudinally on said shaft without turning the shaft so that movement of said rollers along said shaft will not turn the worm gear and therefore the timed relationship between said first and second pair of rollers is maintained upon movement of the second pair of rollers inthe direction of paper travel.

10. The device of claim 1 wherein said second pair of rollers is movable as a unit in the direction of paper travel; and said second pair of rollers is operatively associated With said driven shaft by means of a worm gear collar slidable longitudinally on said shaft without turning about the shaft so that movement of said rollers along said shaft will not turn the worm gear and therefore the timed relationship between said first and second pairs of rollers, is maintained upon movement of the second pair of rollers in the direction olf paper travel.

References Cited in the le of this patent UNITED STATES PATENTS 2,344,720 OConnell Mar. 2l, 1944 2,375,542 Euth May 8, 1945 2,380,949 Davidson Aug. 7, 1945 2,513,093 Hageman June 27, 1950 2,899,871 Auer Aug.- 18, 1959 

1. A BURSTING MACHINE FOR BURSTING CONTINUOUS FORMS OF STATIONERY INTO FORM LENGTHS BETWEEN TRANSVERSE LINES OF WEAKENING, COMPRISING: A FRAME, A FIRST PAIR OF DRIVEN COACTING ROLLERS IN SAID FRAME, SAID FIRST PAIR OF DRIVEN ROLLERS HAVING SURFACES NORMALLY IN CONTACT WITH A PLURALITY OF LONGITUDINALLY EXTENDING RECESSES AND BEING GEARED TOGETHER FOR ROTATION IN A COMMON PERIPHERAL RATE; A DRIVEN SHAFT OPERATIVELY ASSOCIATED WITH SAID FIRST PAIR OF ROLLERS AND EXTENDING PERPENDICULAR TO THE LONGITUDINAL AXIS OF SAID ROLLERS; A SECOND PAIR OF COACTING ROLLERS OPERATIVELY ASSOCIATED WITH SAID DRIVEN SHAFT AND DRIVEN AT A REDUCED SPEED RELATIVE TO SAID FIRST ROLLERS, SAID SECOND PAIR OF ROLLERS ALSO HAVING SURFACES NORMALLY IN CONTACT AND ALSO GEARED TOGETHER FOR ROTATION AT A COMMON PERIPHERAL SPEED, SAID SECOND PAIR OF ROLLERS ALSO HAVING A PLURALITY OF LONGITUDINALLY EXTENDING RECESSES OF A NUMBER 